In general, a vehicle may be started by a driver using a vehicle key, and in addition, by various other methods of starting technologies such as touch panel, button method and remote controlled starting method. Meantime, technologies for preventing safety accidents caused by vehicle operation by a driver in an inadequate state for driving with regard to starting of a vehicle have been developed. For example, a Korean Registered Patent No.: 10-0816249 entitled as “apparatus for preventing drunken driving” has been disclosed in which an alcohol density of a driver is measured using breath of a driver and a rotation of a key is allowed according to the measured density of alcohol to prevent the drunken driving.
However, the conventional technologies suffer from disadvantages because the breath of a driver is used to make measurement inaccurate, it provides a discomfort in the course of a driver inputting a breath of the driver and it is difficult to apply due to changed structure of key box.